1、Wuchereria bancrofti(班氏吴策线虫),Brugia malayi (马来布鲁线虫),Filaria(丝 虫),Adult worm,The adult worms of Wuchereria bancrofti and Brugia malayi are very similar in morpholog,Microfilaria (微丝蚴),体态,头间隙,体核,尾核,班氏丝虫微丝蚴,马来丝虫微丝蚴,前进,班氏丝虫微丝蚴,马来丝虫微丝蚴,体 态,头间隙,班氏丝虫微丝蚴,马来丝虫微丝蚴,班氏丝虫微丝蚴,马来丝虫微丝蚴,体核,班氏丝虫微丝蚴,马来丝虫微丝蚴,尾核,Life cy
2、cle (生活史),腊肠期幼虫 （胸肌）,微丝蚴（外周血液）,1.在蚊体内发育,在蚊体内发育的特点：,1、幼虫仅进行发育并无增殖；,2、患者血液中微丝蚴的密度须达到15条/20l以上，才能使蚊受染，多于100条/20l,常可致蚊死亡；,3、微丝蚴在蚊体内发育的时间与温度、湿度有关，最适合湿度为2530。C，相对湿度为70%90%。,成虫 （淋巴系统）,微丝蚴 （淋巴系统血液）,感染期幼虫（蚊下唇）,2.在人体内发育,微丝蚴在人体外周血液中的出现有一定的周期性，一般为夜多昼少，白天它们停留在肺毛细血管，夜晚则出现于外周血液。,夜现高峰时间：,班氏微丝蚴,马来微丝蚴,晚10时至次晨2时,晚8时至次
3、晨4时,Nocturnal periodicity(夜现周期性),班氏丝虫,马来丝虫,两种丝虫生活史比较,三、致病（pathogenesis),血中无微丝蚴,肺或淋巴结活检可查到微丝蚴,无症状，外周血中有微丝蚴,微丝蚴血症,隐性丝虫病,急性淋巴管炎、丹毒样皮炎、丝虫热,慢性阻塞期,象皮肿鞘膜积液乳糜尿,录像,四、诊断（diagnosis),病原学诊断,血检时间：,晚9时至次晨2时,血检微丝蚴,尿液与体液检微丝蚴,厚血膜法,五、流行与防治(Endemity and Prevention),海群生药盐,传染源,防治,传播途径,微丝蚴血症者 急性期病人,录像,第十二章 吸 虫,第一节 概 论,（Tr
4、ematoda ),2、有口、腹吸盘；,3、同体(hermaphroditic) （血吸虫除外）；,4、无体腔；,5、消化系统不完整、无肛门；,1、外形：舌状或叶片状、背腹扁平（血吸虫除外）；,一、形态 (morphology),一般特征：,前进,卵巢,子宫,睾丸,睾丸,卵 黄 腺,睾丸,睾丸,子宫,卫氏并殖吸虫,布氏姜片虫,日本血吸虫,口吸盘,口,消化系统：,焰细胞,（开口于虫体末端）,排泄系统：,原肾单位,卵巢,性生殖系统：,性生殖系统：,睾丸,二、生活史（life cycle),有性世代,无性世代,终宿主,毛蚴,卵,中间宿主,Miracidium(毛蚴) Sporocyst (胞蚴) R
5、edia (雷蚴) Cercaria(尾蚴) Metacercaria(囊蚴),Clonorchis.sinensis(华支睾吸虫),Chinese Liver Fluke or Oriental Liver fluker Found from the biliary passage of a Chinese in Calcutta, India in 1874 firstly. Common in Asia (China, Korea and Japan) Clonorchiasis (肝吸虫病),Clonorchis sinensis adult(华支睾吸虫成虫),Spindloid me
6、asuring about 16 by 4 mm,Clonorchis sinensis egg,Measure 29 by 16 micrometers(Smallest egg in helminthic egg ) Light-buble shaped Operculated Having a small konb Well-developed miracidium,Embryonated eggs are passed in feces,Eggs are ingested by a suitable snail intermediate host,The cercariae are r
7、eleased from the snail and penetrate the flesh of freshwater fish and encyst as metacercariae,Metacercariae are ingested by human host,Metacercariae excyst in the duodenum ascend the biliary tract and mature there,Pathogenesis,Clinical manifestation,In the acute phase, abdominal pain, nausea, diarrh
8、ea, and eosinophilia can occur. In long-standing infections, cholangitis, cholelithiasis, pancreatitis, and cholangiocarcinoma can develop, which may be fatal.,Definitive diagnosis,Finding eggs in the feces (egg-concentration method ,深沉集卵法) Finding eggs in duodenal aspirate,Epidemiology,Infection so
9、urce: human ,dogs,cats and rats Eggs are passed into water First and second intermediate host in water Eating raw fish with metacercariae(囊蚴),Treatment and control,Praziquantel and albendazole has proven of value. Fish should be cooked well before consumption. Feces must be treated before disposal.,
10、流行,预防,Fasciolopsis buski(布氏姜片虫),The largest intestinal fluke of humans . A parasite of central and southeast Asia.,Fasciolopsis buski adult.,Fasciolopsis buski egg.,130 to 159 m by 78 to 98 m ellipsoidal indistinct operculum thin shell undeveloped germinal cell,Life cycle of Fasciolopsis buski.,毛蚴,P
11、athogenesis,Physical injury to the intestinal mucosa Metabolic product Allergic reaction,Most infections are light and asymptomatic In heavier infections, symptoms include diarrhea, abdominal pain, fever, ascites, anasarca and intestinal obstruction.,Clinical manifestation,Microscopic identification
12、 of eggs, ormore rarely of the adult flukes, in the stool or vomitus.,Definitive diagnosis,直接涂片法,Epidemiology and Prevention,Asia and the Indian subcontinentEspecially in areas where humans raise pigs and consume freshwater plants. Change food habits Praziquantel is the drug of choice .,Paragonimus
13、westermani,(卫氏并殖吸虫),Paragonimus 50 species of paragonimus, P. westermani (the oriental lung fluke) is the most important 1878, first description in tiger; in 1880, first case found in Taiwan Paragonimiasis (parasitic zoonoses),Paragonimus westermani adult: a plump reddish brown oval worm measuring 1
14、0 by 4 mm .,Average size :85 m by 53 m Yellow-brown, ovoidal or elongate Thickshell ,asymmetrical Operculum is clearly visible,Egg of Paragonimus westermani,Life Cycle of of Paragonimus westermani,毛蚴,体内移行,穿肠壁,Paratentic host,Pathogenesis and Clinical Features,diarrhea, abdominal pain, fever, cough,
15、urticaria, hepatosplenomegaly, pulmonary abnormalities, and eosinophilia,invasion and migration of young flukes,cough, expectoration of discolored sputum, hemoptysis, and chest radiographic abnormalities,residing of adult in tissue (lung),Ectopic lesion(异位损害),Definitive diagnosis,Finding eggs in sto
16、ol or sputum.(直接涂片法) Finding larvae in tissue.(组织活检法),Epidemiology and Prevention,流行,Praziquantel(吡喹酮),Eating raw crab with metacerariae (生吃溪蟹),卵巢,子宫,睾丸,卵 黄 腺,一、形态,成虫,斯氏狸殖吸虫,Pagumogonimus skrjabini,卫氏并殖吸虫,第一中间宿主,川卷螺,斯氏狸殖吸虫,拟钉螺,终宿主,人，犬，虎,果子狸,幼虫移行症,Schistosome（血吸虫）,寄生于人体的血吸虫主要有6种:,S. Japonicum (日本血吸虫)
17、 S. haematobium (埃及血吸虫) S. mansoni (曼氏血吸虫) S. intercalatum (间插血吸虫) S. mekongi (湄公血吸虫) S. malayensis (马来血吸虫),日本血吸虫、埃及血吸虫和曼氏血吸虫引起的血吸病流行范围最广危害最大. 我国主要是日本血吸虫流行.,血吸虫病是危害我国农民身体健康最严重的寄生虫病。建国初期严重流行区大量人群死亡，田园荒芜，一片悲惨景象，有诗为证：,绿水青山枉自多，华佗无奈小虫何！ 千村薜荔人遗矢, 万户萧疏鬼唱歌.,虽然我国血吸虫的防治取得了很大的成效,但危害仍很严重,江西为重流行区.,为世界六大热带病之一,我国五
18、大寄生虫病之一。,日本片山., 1904年日本学者Katsurada检查猫粪便， 发现虫卵，在猫的门静脉中发现成虫。, 1905年Logan在湖南常德县一名18岁的农民粪便中首次检出日本血吸虫卵。,日本血吸虫的发现:,columniform(圆柱状形) dioecious (雌雄异体),Adult of Schistosoma. japonicum,gynecophoral canal,reproductive system of the male,testis(睾丸),reproductive system of the male,ovary(卵巢),medium size (中等大小),e
19、lliptic(椭圆形),light yellow (淡黄色),miracidium (毛蚴),thin and symmetrical (厚薄均匀),no operculum (无卵盖) lateral spine(一侧有一小棘),egg,immune complex,lateral spine,1.Adults reside in mesenteric venles and females lay eggs,2.Eggs are passed in feces and hatch releasing miracidia in water .,3.Miracidia penetrate sn
20、ail tissue and develops into mother sporocysts 、daughter sporocysts and cercariae step by step.,4.Cercariae are released by snail into water and penetrate the skin of humans and then become chistosomulae .,5.Chistosomulae migrate to mesenteric venles by circulation and mature into adults .,life cylc
21、e (生活史),母胞蚴,成熟虫卵在组织中的寿命为1011天。,从尾蚴钻入皮肤到虫体成熟并产卵约需24天。,成虫的平均寿命约为4.5年。,？,录像,outlets of eggs,4、reach the brain 、the lung and other tissues.,2、the majority stay in intestinal tissue .,3、being passed in feces .,1、get to the liver .,why?,Why can eggs be passed in feces？,录像,1、产卵于肠壁的小血管的未梢，成熟的虫卵分泌SEA，使肠壁组织 发
22、生炎症坏死。,2、在血流压力、肠蠕动和腹内压增加的情况下、虫卵随破溃的坏死组织落入肠腔，随粪便排出体外。,migration route,肠系膜A,(定居、交配产卵）,infective manner：,infective stage ：,lodging：,needing for migration,intermediate host ：,definitive host:,human,Oncomelania hupensis,cercaria,contacting with epidemic water by skin,mesenteric venules,请比较血吸虫生活史与钩虫生活史的异同
23、点,characters of life cycle,reservior host:,domestic animals(pig 、 cattle) and feral animals,宿主感染血吸虫后,活的成虫可产生一定程度的抵抗力，其对原有成虫不起杀伤作用，但对再次入侵的童虫具有一定的杀伤作用。,immunity(免疫),native immunity,acquired immunity,concomitant immunity(伴随免疫),style,immuity evasion(免疫逃避),(1)抗原伪装和抗原模拟,(2)表面受体学说,(3)表面抗原的表达缺失,思考题:,(1)初次感染
24、两周后，再次接触疫水时这种免疫力会不会产生作用?,(2)为什么在疫区年龄较大的儿童中有的高度接触疫水却呈现低度再感染的现象?,cercaria:,chistosomulum:,adult:,egg:,pathogenesis(致病),cercarial dermatitis(尾蚴性皮炎),egg granulomata(虫卵肉芽肿),vascular inflammation(血管炎),phlebitis(静脉炎),成熟虫卵毛蚴分泌SEA,虫卵肉芽肿及纤维化形成的机制：,肉芽肿有什么利和弊?,为什么血吸虫病人可出现肝硬化?,symptom,acute schistosomiasis(急性血吸虫
25、病),chronic schistosomiasis(慢性血吸虫病),terminal schistosomiasis(晚期血吸虫病),ectopic schistosomiasis(异位血吸虫病),录像,急性期表现,粘液脓血便,荨麻疹,慢性期表现,以腹痛腹泻常见, 时发时愈,常有肝脾肿大，肝质地稍硬,无压痛.,无症状型,有症状型,一般无症状,少数可有轻度的肝或脾大.,晚期表现,日本血吸虫病晚期患者,异位血吸虫病,临床表现,血吸虫卵可通过哪些途径到达脑部或肺部呢?,diagnosis,(1) 临床诊断,病史,临床表现,发热、腹痛、腹泻等,来自疫区,是否接触过疫水.,(2)病原学诊断,(3)免疫
26、学诊断,急性期病人：沉淀聚卵法+孵化法,晚期病人：直肠粘膜活检法,诊断,COPT、IHA、ELASE方法等,菲律宾,泰国,印度尼西亚,中国,epidemiology,建国初期我国血吸虫病的分布,1200万,目前我国消灭血吸虫病的省市,目前我国血吸虫病的分布,69万,江西是重流行区, 主要分布在鄱阳湖邻县波阳、余干、星子、都昌、永修、彭泽、进贤、新建等。还有九江庐山区、上饶、玉山等地.,建国初期江西有血吸虫病人270多万。到2001年止,江西仍有血吸病人11万左右, （10万为慢性病人）,实有钉螺面积701178/km2（685804 /km2 为湖沼型）。,平原水网型,山丘型,湖沼型,流行区类型,7.9,10,82 . 1,传染源,病人和病畜(牛),传播途径,录像,流行环节,基本方针: 积极防治、综合措施、因时因地制宜.,控制传染源,录像,切断传播途径,保护易感人群,prevention,防治中存在的问题,疫区自然环境并未改善。,血吸虫的传播条件依然存在。,洪涝灾害使螺情、疫情回升。,疫区生活生产、方式没有根本改变。,疫区家畜放养、重复感染、不易控制。,新疫区的出现。,
